Internal-combustion engine



G. e. WESTERFIELD.

INTERNAL comausnow ENGINE.

APPLICATION FILED APR. 19. 1920. 1,421,878, Patented July 4, 1922.

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INTERNAL COMBUSTION ENGINE. APPLICATION FILED APR. 19, 1920. I I 1,421,878 Patented July 4, 1922.

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WOT/M 0136 G. G. WESTERFIELD.

INTERNAL COMBUSTION ENGINE.

APPLICATION FILED APR-19,4920.

1,42 1, 7 Patented July '4, 1922..

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En el 0} Power avweutoz Gran ville Cg 715552711411 alt Emmy To all whom it may concern:

UNITED STATES.

GRANVILLE G. WESTERFIELD, 0]! INDIANAPOLIS, INDIANA.

INTERNAL-COMBUSTION ENGINE.

Specification of Letters Patent. Patented J ly 4 1922.

Application 'fi1ed,April 19, 1920. Serial No. 874,984.

Be it known that I, GRANVILLE G. WEs'rnR- FIELD, a citizen of the United States, residing at Indianapolis, in the county of Marion and State of Indiana, have invented a new and useful Internal-Combustion Engine, of which the following is a specification.

It is the object of my invention to vary the compression space of an internal combustion engine to suit different fuels and different conditions of operation, by varying the position of the piston at the end of the compression stroke as desired; and to produce a power stroke which is longer than the intake stroke so that at the ends of the power strokes a supplemental exhaust portin the cylinder wall is uncovered to permit the burned gases to escape after substantially the'full energy from their expansion has been obtained and to improve the scavenging, and to obviate the necessity for opening the main exhaust valve while it is under pressure and before the entire'energy from the expanding gases has been obtained.

In attaining this object, instead of connecting the connecting rod of each piston directly to a crank pin having a simplecircular motion as in the ordinary engine, I

connect it to an eccentric (or crank pin) on the main crank pin, which eccentric in addition to the circular motion about the axis of the crank shaft also has a superposed circular motion about the axis of the main crank pin, the superposed motion in the preferred form of my invention having half the angular velocity of the main crank pin. By maintaining the proper relation between the two motions, the piston is made to move further toward the crank shaft on the power strokes than on the intake strokes, by twice the distance by which the eccentric is offset from the axis of the crank pin, but the piston is brought to the same or nearly the same position at the ends of the compression and exhaust strokes. In addition, by shifting the angle at which the eccentric is offset from the axis of the main crank pin for a given position of the latter, which shifting I provide means for obtaining, the posltion of the piston in the cylinder at the ends of the compression and exhaust strokes may be varied as desired, thus controlling the size of the compression space, without materially varying the positions which the piston takes at the ends of the power and intake strokes.

The accompanying drawings illustrate my invention. Fig. 1 is a simple diagrammatic f showing the parts at the crank shaft, with one pair of associated connecting rods and .part of one piston and the operating mechanism for shifting the sun gear to vary the compression space; Figs. 4 to 7 inclusive are diagrams showing the different positions of the piston in a pair of cylinders at ends of successive strokes throughout the four strokes of the cycle, with the sun gear remaining in fixed position; and Figs. 8 and 9 are similar diagrams showing the effect of shifting the sun gear. I The crank shaft 10 for the four-cylinder engine shown is provided at its two ends with crank pins 11 and 12 respectively, which crank pins and shaft may be of any desired construction, though as shown the crank pins are carried by fly wheels 13 and 14 fixed on the shaft 10 and suitably counterweighted at 15 (Fig. 2). The crank pins 11 and 12 are diametrically offset with respect to the crank shaft axis (Fig. 1), and each crank pin is associated with the connecting rods from the pistons of two diametpair of cylinders is the same as that for the.

other, so that it will be necessary to describe only the connections at one crank pin, say the crank pin 11. I

On this crank pin'll isrotatably mounted a sleeve formed of a gear 21, a middle eccentric portion 22, and two eccentric portions 23 located on opposite sides of the middle eccentric portion 22. The two eccentric portions 23 are exactly alike, with a common axis, and carry the forked crank-shaft end 'of the connecting rod 25 associated with the piston 27 in the cylinder 17. The middle eccentric portion 22 carries the crankshaft end of the connectin rod 26 associated with the piston 28 in fihe cylinder 18. The crank-shaft end of the connecting rod 26 is thus located between the prongs of the crank-shaft end of the connecting rod 25, to equalize their action. The common axis A of the two eccentrics 23 and the axis of theeccentric 22 are offset from the axis C of the-crankpin 11 by e ual amounts, but

I relationship,

in directions at rightvang es to each other,

as is clear from Figs. 1 and 4 to 9 inclusive. 3 This right-angle I relationship between the ,ofis'ettings of the axes A and B is a fixed though the direction of such 'ofl'settings with relation to the crank pin and th'ecrank shaft varies in the operationv of'the' engine and is also variable, under suitable control, tovary the compression space,aswill'hereinafter appear. .As shown,

a f "this control is manual, and is obtained by moving the gear 21, which isa planet gear,

about its axis, which is the axis C.

.The planet gear 21 is connected to .a sun gear ;30'which is co-axial with the crank haft 1'0 but. is normally fixed though cumferentially adjustable. This sun earI does not rotate with the crank sha order that the planet gear 21 may rotate in space at half crank-shaft speed, as' is desired in the preferred form of my lIlVel'l: tion, such planet gear. is twice the diameter of the sun gear 30, as is clear from Figs; '1, 2 and 3, and is connected to the sun gear through a pair .of idle!- gears 31 carried by a shaft 32 mounted in the fly wheel 13, the two idler gears of suohshaft meshing respectively with the sun gear 30 and. the planet gear 21, which are located on opposite sides of such fly wheel. In Fig. 2 the shaft 10 is partly broken away to show the idler gear 31 beneath-it. With this arrangement, the planet gear and the eccentric carried thereby rotate in space 180 about the axis C for every revolution of the crank shaft 10.

"The sun gear 30 is adjustable circumferentially through a limited range, to vary the position of the axes A and B independently of the movement of the crank shaft 10.- This adjustment of the sun gear 30 is obtained in any desired way. As shown, such sun gear is fixed to a sleeve 35, from which proects an arm 36 carrying a gear segment 37,

with which meshes a suitable pinion 38 i movable,if desired through several rotations,

by an arm 39 telescopically extensible so that a pin 40 carried by the outer end there of may be made to travel in a path fixedby artitions 41 on a fixed plate 42 and be rought into co-operation with and held by any one of the holes 43 provided in such plate and arranged in two or more annylar series interconnected by the grooves provided by the partitions 41.

' With the sun gear 30 in about its middle position of adjustment, in which position it is assumed to be in Figs. 1 to 7 inclusive, when the crank pin 11 is' in the axial line of the two cylinders 17 and 18 and toward the cylinder 17, as indicated in Figsrl, 2, 3, 4, and 6, the axis B of the eccentric 22 .of the intake stroke.

is oifset from theaxis-C subst antially'in such axial line of the two cylinders, while the axis A of the eccentrics 23 is offset fromv the axis C at right angles to such axial line. With the crank pin 11 toward the cylinder 18, 'as indicated in Figs. 5 and 7, the offsettingof the axis A is in the axial line of the two cylinders, and that of the axis B is' at right angles to such line. This offsetting of each respective axis A and B is in opposite directions from the axis C at the ends of alternate revolutions of the crank shaft,

as indicated by a comparison of Figs. 4 and 6 or of F igs. 5 and 7. Thus as the engine operates, the eccentrics 22 and 23 as actuated by the planet gear-21 rotate in space .90 while the crank shaft rotates 180. This is inclusive. In these figures, the piston 27. is shown in the positions it has at the .ends

intake strokes, respectively; while the piston 28 is shown in the ends of the power, ex aust, intake, and compression strokes, respectively. In other words, for this pair of cylinders, the piston 28 is one quarterof a cycle ahead of the piston 27; while the pistons for the cylinders 19 and '20,- which pistons are connected to the crank pin 12, are, respectively one quarter and one half ofa cycle behind the piston 27. When the crank shaft makes one completerotation, the eccentrics 22 and 23 are rotated 180 in space. Therefore, starting from a point where one of the axes'A and B is-displaced along the axial line of the associated cylinder in one direction fromthe axis C, as the axis B is displaced to the right from the axis C in Fig. 4, after a rotation of the crank shaft through 360, or to the position shown in Fig. v6, the displacement of such eccentric axis is just opposite along the axial line of the cylinders from theaxis C from what it was at the start; which means that at the ends of the power and intake strokes the iston connected to that eccentric is in different longitudinal positions in its cylinder, thedifi'erence being equal to twice the distance by which the eccentric axis is ositions it has at the indicated diagrammatically in Figs. 4 to 7 of the compression, power, exhaust, and

offset from the axis C, so that at the end. 5

site side of the axial line of the cylinders without any difference longitudinally of such axial line; which means that at the ends" of the compression and exhaust' strokes the piston connected tothat eccentric'is nthe same longitudinal positionin'its cylinder. This makes the power stroke of -ea'ch stroke the supplemental exhaust 'ports' 45-in ;the cylinder wall areuncovered to permit "the burned gases, to escape while thejmain" exhaustvalve'gforthe exhaustport 47- is still closed, so that it is possible bythus relieving] 75 piston longer than the-intake strokes. As at the end ofthe compression stroke of a piston its associated eccentric axis (the ax1s.A for the piston 27 in Fig. 4) isidisplaced from the axis Ctoxone side of the axial line of the'cylinders, an adjustment of the sun gear 30 by the manipulation ofthe I arm .39 shifts'such eccentric axis around the axis C in the small circle D;- but the arc of movement of the axis A is then nearly parallel to' the axial line of the cylinders so that this results in a longitudinal movement of the piston 27 either to increase the size of the compression space E as indicated in Fig. 8 for an adjustment of the sun gear 30.1n 20' one direction or to decrease the size of such compression space as indicated in Fig. 9 for an adjustment of the sun gear in the other direction from the middle position which it is assumed to have in Figs. 1 to 7 inclusive. Thus the size of the compression space is varied to suit different fuels. This adjustment of the sun gear does not greatly affect the piston position at the ends of the power and intake strokes, however, because of the.

movement of the associated eccentric axis, say the axis B for the piston 28 in Figs. 4 and 6, is in parts of the circle D which are nearly at right angles to the axial line of the cylinders so that only a very small component of the movement of .the axis B is longitudinal of such axial line. In consequence, the position of the piston at the ends of the power and intake strokes is nearly the same longitudinally of the cylinders for all positions of adjustment of the sun gear 30, as is clear from a comparison ofthe positions of the piston 28 in Figs. 4, 8, and 9.

In operation, as in all internal combustion engines, the useof a fuel which volatilizes at low temperature facilitates starting, as is well recognized in internal combustion practice, and for this reason such a fuel is preferably used for starting. Such a fuel, however, operates first with-rather low compression, in order to permit easy cranking'or starting and to avoid pre-ignition, and so for starting with such a fuel the sun gear is adjusted to give a large compression space E, as indicated in Fig. 8. The engine is set into operation in the usual manner, and the several pistons go through their four-stroke cycles. Considering the piston 27, for instance: on its intake 'stroke it draws in a charge through the intake port 46, the intake stroke being of such length that the supplemental exhaust 45 in the cylinder wall is not uncovered; then on the compression stroke the charge thus drawn in is compressed to a point determined by the size of the compression space E as set by the adj ustpowerfstrok, I which is longer than the" in ment of the Sanger thenthe'explosidn"a is produced, and the 'pistonis' moved-on its 5;

take-stroke sothatat the end of the .p'owe the pressure in the cylinder-before the end' of the power stroke to get- -tlie full-expan- I sionof the burning gasesbefore allowing;

lieved, the piston moves on its exhauststroke them'fito escape; and then, themain exhaust. valve in the exhaust port-47 having been opened, which opening is easy becausethe Q. pressure on such exhaust valve has been -re-'" t0 expel the remainin b gas in the cylinder throughthe exhaust port 47', su h.

expulsion being with the burned gases under greatly reduced pressure by reason of the earlier escape through the port 45, so that-a more complete exhaustion of the burned l in operation long enough to be suitably but which operatesbest at higher compresgases is obtained. After the engine has been warmed, the fuel may be changed to one which volatilizes at a higher temperature,-'-

sions,.and so when the change of-fuel is made the sun gear 30 is adjusted to get the I Inthe four-cylinder engine shown, with two pairs of opposed cylinders respectively at opposite ends of the crank-shaft 10, the order of firing of the cylinders is 18-17- 19-20. This produces-a substantially balanced action. Each pair of cylinders has its own" controlling sun gear 30, with the connections therefrom to the associated planet gear and eccentrics, and the two sun gears may be controlled either separately or jointly as desired, though preferably jointly by a single controlling arm 39. The power from the crank shaft is conveniently taken off at an intermediate point, between the two pairs of cylinders, as by a central gear 50. fixed on such shaft. 1

a 1.1 .claim as my invention:

L/In an internal combustion engine, the combination of a cylin'der, a piston movable therein, a crank 1 shaft having a crank;.,pin,-

- the crank pin axis at a different-angular speed from that-of the crank shaft and so that it normally arrives at the same position at the end of each alternate revolution of the crank shaft, a connecting rod connecting said eccentric to said piston, and means for adjusting said eccentric about the axis of said crank pin while the engine is in operation to vary the position of the piston in the cylinder at the end of the compression stroke thereof.

2. In an internal combustion engine, the combination of a cylinder, a piston movable in said cylinder, a crank shaft, an eccentric carried by said crank shaft, a connecting rod between said eccentric and said piston, said eccentric being associated with said crank shaft so that during the rotation of the crank shaft it has a rotary movement about an axis eccentric to itself and eccentric to the crank shaft but rotatable with the crank shaft, and gearing for producing such rotary movement of said eccentric at an angular velocity half that of the crank shaft, said gearing being manually operable independently of the crank-shaft movement.

3. In an internal combustion engine, the combination of a cylinder, a piston movable in said cylinder, a crank shaft, an eccentric carried by said crank shaft, a connecting rod between said eccentric and said piston, said eccentric being associated with said crank shaft so that it is adjustable about an axis eccentric to itself and to the crank shaft, means for adjusting said eccentric about such axis to vary the compression space of said cylinder.

4. In an internal combustion. engine, the combination of a cylinder, 3. piston movable therein, a crank shaft, a sleeve carried by I said crank shaft and movable about an axis eccentric to the crank shaft, a connecting rod connecting said piston to said sleeve and connected to said sleeve on an axis eccentric to the sleeve axis, a stationary adjustable member concentric with the crank shaft, gearing between said stationary member and said sleeve to produce rotation of the latter about its axis at half the angular speed of the crank shaft, and means for adjusting said stationary member about its axis to vary the position of said sleeve independently of the crank shaft movement.

5. In an internal combustion engine, the combination of a cylinder, a piston movable therein, a crank shaft, a sleeve carried by said crank shaft and movable about an axis eccentric to the crank shaft, a connecting rod connecting said piston to said sleeve and connected to said sleeve on an axis eccentric to the sleeve axis, said sleeve having an external gear fixed thereto, a stationar external adjustable gear concentric wit the crank shaft, said first-named gear being of twice the diameter of the second-named gear, idler gears carried by the crank shaft and meshing with the first-named and secondnamed gears, and means for adjusting said stationary gear about its axis.

6. In an internal combustion engine, the combination of a cylinder, a piston movable therein, a crank shaft having a crank pin, an

eccentric mounted on said crank pin and adjustable around the axis thereof, means for rotating said eccentric in space about the crank pin axis at a different angularspeed from that of the crank shaft and so that it normally arrives at the same position at the end of each alternate revolution of the crank shaft, a connecting rod connecting said eccentric to said piston, and means for adjusting said eccentric about the axis of said crank pin while the engine is in operation.

7. In an internal combustion engine, the combination of a cylinder, a piston movable in said cylinder, a crank shaft, an' eccentric carried by said crank shaft, a connecting rod between said eccentric and said piston, said eccentric being associated with said crank shaft so that during the rotation of the crank shaft it has a-rotary movement about an axis eccentric toitself and eccentric to the crank shaft but rotatable with the crank shaft, and gearing for producing such rotary movement of said eccentric at an angular velocity half that of the crank shaft, said gearing being manually operable independently of the crank-shaft movement.

8. In an internal combustion engine, the combination of a cylinder, a piston movable therein, a crank shaft, a connecting rod connecting said crank shaft to said piston, and gearing for varying the effective length of the crank arm on which said connecting rod is connected to said crank shaft periodically during the operation of the engine to produce a longer average effective len h during the power stroke than during t e suction stroke.

9. In an internal combustion engine, the combination of a cylinder, :1. piston movable therein, a crank shaft, a connecting rod connecting said crank shaft to said piston, and gearing for varying the effective length of the crank arm on which said connecting rod is connected to said crank shaft in a cycle requiring two revolutions of the crank shaft for its completion, and producing a longer average effective length during the power stroke than during the suction stroke.

10. In an internal combustion engine, the combination of a cylinder, a piston movable therein, a crank shaft, a connecting rod connecting said crank shaft to said piston, and gearing for varying the effective length of the crank arm on which said connecting rod is connected to said crank shaft at will to vary the compression space of the cylinder, and also to vary such effective length periodically during the operation of the engine.

11. In an internal combustion engine, the combination of two opposed cylinders, pis-v tons movable therein, 'a crank shaft between rods connecting the respective pistons to said sleeves and connected to said sleeves onaxes which are offset from the sleeve axis atright angles to each other, and means for rotating said sleeve about its axis. i

12. In an internal combustion engine, the combination of two opposed cylinders, pistons movable therein, a crank shaft between said opposed cylinders, a sleeve carried. by

10 said crank shaft and movable about anaxis eccentric to the crank shaft, two connecting rods connecting the respective pistons to said sleeves and connected to said sleeves on axes which are offset from the sleeve axis at I right angles to each other, and means for rotating said sleeve about its axis once for every two crank shaft revolutions "to make alternate complete reciprocations of the two pistons of different length.

GRANVILLE G. WESTERFIELD. 

